1. Field of the Invention
An artificial arm assembly of the type incorporating a plurality of individual drive motors to accommodate a preselected movement of a forearm base relative to an upper arm base, a hand base relative to the forearm base and digits, representing fingers, relative to the hand base.
2. Description of the Prior Art
Artificial members of the human body have reached a relatively sophisticated stage of development in the prior art. As a result, members include artificial arms and artificial hands serving as prosthesis and specifically designed to be operatively attached to the human body in replacement for the missing limb. Specifically with regard to the design and operation of such artifical hands and arm assemblies, including mechanically movable fingers, such are designed to attempt freedom of movement resembling as closely as possible the movement of the natural arm and hand. More specifically, the mechanically movable fingers are intended to enable the user thereof to perform the many gripping functions normally occurring in day-to-day use. One factor is of course operational time required to perform each function. Obviously, such operational time should be minimized in an attempt to normalize the movement and time of such movement relative to the natural limb.
In order to minimize the operational time of artificial limbs and increase and vary the range of movement of such artificial limbs, especially the gripping fingers, it is necessary to provide a drive assembly for the movable element which is efficient.
Representative attempts existing in the prior art to meet the foregoing requirements are varied. Included are pneumatic drive systems which receive the driving energy from high pressure containers or air pressure conduits. Even gas pressure cartridges have been used as the energy supply for artificial limbs. German Patent Publication (DOS) No. 2433710 illustrates a device employing high pressure containers which are rechargeable.
Other known drive assemblies are disclosed in an additional German Patent Publication (DOS) No. 2426711 demonstrating the use of an electric motor connected to the drive means for operating fingers of an artificial hand by means of cord and pulley assemblies. Also, the U.S. Pat. No. 4,188,166 to Moreau demonstrates a small size telemanipulator with a rotatable gripping tool secured to the end thereof. The latter structure is primarily used for a gripping tool rather than as a prosthesis for the replacement of a missing limb. However, the structures are similar in the sense that arm and hand movement and gripping force are intended to duplicate that of a human arm and hand.
Other U.S. patents which demonstrate arm and limb assemblies including a variety of drive means used to accomplish the aforementioned requirements include Motis, U.S. Pat. No. 2,516,791; Fishbein, U.S. Pat. No. 2,537,338; Alderson, U.S. Pat. No. 2,592,842; Motis, U.S. Pat. No. 3,466,944; Yakobson et al, U.S. Pat. No. 3,521,303; Eroyan, U.S. Pat. No. 4,094,016; Moreau, U.S. Pat. No. 4,188,166; Janovsky, U.S. Pat. No. 4,232,405; and Pinson, U.S. Pat. No. 4,246,661.
The structures disclosed in the above noted domestic and foreign patents represent a segment of the prior art of artificial hand and limb assemblies which are specifically designed to improve the range and variety of motions as well as speed of operation and gripping pressure in order to allow a prosthesis structure to more closely resemble the workings of a natural hand and arm.